Hydraulic isotropically-pressurized battery modules

ABSTRACT

Various arrangements of pressurized battery modules are detailed herein. Such a pressurized battery module may include a sealed battery module housing. The pressurized battery module may include multiple pouch cells. Each pouch cell may be located within the sealed battery module housing. The pressurized battery module may further include an insulative oil that is pressurized within the sealed housing. This insulative oil may exert pressure on an external surface of each pouch cell within the pressurized battery module.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/217,002, filed on Dec. 11, 2018, entitled “HydraulicIsotropically-Pressurized Battery Modules,” which is related to U.S.patent application Ser. No. 16/217,010, filed on Dec. 11, 2018, entitled“Hydraulic Isostatic Press Processes for Solid-State Batteries,” theentire disclosures of which are hereby incorporated by reference for allpurposes.

BACKGROUND

Certain types of batteries perform better when pressure is maintainedbetween the batteries' electrolyte, anode, and cathode. Conventionally,to accomplish this, a jig can be used. A jig may include multiple rigidplates that are compressed toward each other using fasteners that extendbetween the rigid plates. The battery may be situated between the rigidplates to receive the compressive force of the jig's plates. Such anarrangement contributes weight and volume to a battery assembly.Further, such pressure may not be uniform due to variances in thethickness of the batteries or flexing of the jig's plates.

SUMMARY

Various embodiments of pressurized battery modules are presented herein.A module may include a sealed battery module housing. A module mayinclude a plurality of pouch cells, wherein each pouch cell is withinthe sealed battery module housing. The module may include a liquid thatis pressurized within the sealed housing, wherein the liquid exertspressure on an external surface of each pouch cell of the plurality ofpouch cells.

Embodiments of pressurized battery modules may include one or more ofthe following features: The liquid may be an electrically-insulativeoil. Each pouch cell of the plurality of pouch cells may be cylindrical.The module may include a plurality of support pillars attached with thesealed battery module housing. Each cylindrical pouch cell of theplurality of pouch cells may be held in place within the sealed batterymodule housing by a subset of support pillars of the plurality ofsupport pillars. The liquid may exert isotropic pressure to a curvedsidewall of each cylindrical pouch cell of the plurality of pouch cells.The liquid may exert isotropic pressure on a top, a bottom, and a curvedsidewall of each cylindrical pouch cell of the plurality of pouch cells.The module may further include a plurality of leads and a polymer-basedsealant. The polymer-based sealant may create a seal for each pouch cellof the plurality of pouch cells through which a lead of the plurality ofleads passes between the pouch cell and an external environment outsideof the sealed battery module housing. The module may include a pluralityof cylindrical poles, wherein a cylindrical pole of the plurality ofcylindrical poles is present in a center of each cylindrical pouch cellof the plurality of pouch cells. The module may include a plurality ofcylindrical poles, wherein an airspace is present in a center of eachcylindrical pouch cell of the plurality of cylindrical pouch cells. Themodule may include a plurality of pouch cell arrays, wherein each pouchcell array comprises multiple pouch cells of the plurality of pouchcells pressed together. The module may include a first insulator plateand a second insulator plate, wherein the first insulator plate and thesecond insulator plate support each pouch cell array within the sealedbattery module housing. Each pouch cell may include a sulfur-basedsolid-state electrolyte.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of variousembodiments may be realized by reference to the following figures. Inthe appended figures, similar components or features may have the samereference label. Further, various components of the same type may bedistinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If only the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

FIG. 1 illustrates an embodiment of a cylindrical battery cell pouch.

FIG. 2 illustrates an embodiment of a cylindrical battery cell pouchcross section.

FIG. 3 illustrates an embodiment of a pressurized battery module thatincludes cylindrical battery cell pouches.

FIG. 4 illustrates an embodiment of a planar battery cell pouch array.

FIG. 5 illustrates an embodiment of a planar battery cell pouch arraycross section.

FIG. 6 illustrates another embodiment of a planar battery cell poucharray cross section.

FIG. 7 illustrates an embodiment of a pressurized battery module thatincludes planar battery cell pouch arrays.

FIG. 8 illustrates a side view of an embodiment of a battery cellactivation system.

FIG. 9 illustrates a top view of an embodiment of a battery cellactivation system.

FIG. 10 illustrates a side view of another embodiment of a battery cellactivation system.

FIG. 11 illustrates an embodiment of a method for activating a batterycell by increasing an amount of contact between an electrolyte andactive materials of a battery cell.

DETAILED DESCRIPTION

Various types of batteries may function more effectively when pressureis applied to press the active components (i.e., cathode and anode) of abattery against a separator between the active components and theelectrolyte. Further, such types of battery cells may also function moreeffectively when operated at a relatively high temperature (e.g., above60° C.). Pressure and heat may be isotropically distributed to batterycells by pressurizing a thermally-conductive electrically-insulativeliquid that surrounds or partially surrounds each battery cell. By usinga thermally-conductive electrically-insulative liquid, a consistentpressure may be applied to each battery cell and thermal energy may beevenly and efficiently dispersed among battery cells. For example, suchbatteries, which can be rechargeable, may be useful for use in poweringpropulsion of electric vehicles. Electric vehicles can benefits fromlightweight batteries that have a high energy density and power density.

Different forms of battery cell pouches may be suspended withinpressurized liquid, such as oil. Cylindrical battery cell pouches mayeach be supported by multiple support pillars. The pressurized oil mayprovide a same pressure on each cylinder's curved surface (and,possibly, the cylinder's top circular planar surface and/or bottomcircular planar surface). Planar battery cell pouches may be stacked toform battery pouch cell arrays. The pressurized oil may provide a samepressure on each of the sides of the planar battery cell pouches.Alternatively, pressure exerted by the oil on an external surface of afirst battery cell pouch may cause the first battery cell pouch to pressagainst a second battery cell pouch, effectively resulting in eachbattery cell pouch of a battery cell pouch array being compressedtogether by the pressurized oil.

The battery cell pouches and the pressurized oil may be housed within asealed housing. The sealed housing may maintain the pressurization ofthe oil, and, thus, the oil does not need to be actively pressurizedwithin the housing. The oil may be actively or passively circulatedwithin the battery housing to distribute heat evenly. In someembodiments, an active heating element heats the sealed housing orpressurized oil to a temperature at which the battery cells functionmore effectively (e.g., greater energy density, greater power density).

FIG. 1 illustrates an embodiment of a cylindrical pouch cell system 100.The illustrated view of cylindrical pouch cell system 100 is from above.Cylindrical pouch cell system 100 may include: cylindrical pouch cell110; supports 120; and pressurized liquid 130. Cylindrical pouch cell110 may include a jelly-roll style or cylindrical-style activecomponents 112. Active components can include a cathode, an anode, andan electrolyte. Cylindrical pouch cell 110 may be a solid-state battery,meaning the cathode, anode are solid, rather than liquid or polymerbased. For example, cylindrical pouch cell 110 may use a sulfur-basedsolid-state electrolyte or Li-ion conductive polymer electrolyte.Cylindrical pouch cell 110 may be a sulfur oxide battery pouch. Othertypes of battery pouches may be possible, such as non-solid statebatteries.

Active components 112 may be surrounded by deformable pouch housing 116.Deformable pouch housing 116 may allow pressure exerted on an externalsurface of cylindrical pouch cell 110 to be transferred to activecomponents 112, thus causing the anode, cathode, and electrolyte to bepressed together. In the center of cylindrical pouch cell 110, centerregion 114 may be presented. Therefore, deformable pouch housing 116 maynot be sufficiently rigid such that is can resist the pressure exertedby pressurized liquid without somewhat deforming. Deformable pouchhousing 116 (and thus cylindrical pouch cell 110) may have a diameter ofbetween 15 mm and 50 mm. Center region 114 may be airspace or may bepole, such as a metallic pole.

To hold cylindrical pouch cell 110 in a particular location andorientation, multiple supports 120 may be present. In the illustratedembodiment three cylindrical support pillars are present: support 120-1,support 120-2, and support 120-3. These supports may be insulative.These supports may be anchored on the top and bottom to a sealed housingin which cylindrical pouch cell 110 is located. Therefore, in additionto holding cylindrical pouch cell 110 in a particular location, supports120 may contribute to the structural rigidity of the sealed housing.While the illustrated embodiment of FIG. 1 illustrates three supports120 dispersed at approximately 120° around cylindrical pouch cell 110,in other embodiments, greater or fewer numbers of supports may be usedto hold cylindrical pouch cell 110 in place. For example, a singledifferently shaped support may be used to hold cylindrical pouch cell110 in place.

Surrounding cylindrical pouch cell 110 may be a thermally-conductiveelectrically-insulative pressurized liquid 130, such as an oil. This oilmay be pressurized such that hydraulic pressure is isotropically appliedto deformable pouch housing 116, at least along the curved surface ofthe cylinder. This isotropic pressure exerted by pressurized liquid 130is visualized by arrows 140. In some embodiments, pressurized liquid 130is pressurized such that at least 1 MPa (145 pound-force per squareinch). Such a pressure may cause the electrolyte within activecomponents 112 to remain pressed against the cathode and anode.

Illustrated in FIG. 1 is a location of cross section 200. FIG. 2illustrates cylindrical battery cell pouch cross section 200. Crosssection 200 illustrates a side view of a cross section of cylindricalpouch cell 110. Cross section 200 illustrates: support 120-1; activecomponents 112; center region 114; pressurized liquid 130; sealedhousing top 210; sealed housing bottom 220; insulative seal 230; top gapspaces 240; leads 250; base insulators 260; and bottom gap spaces 270. Asingle support 120-1 is visible due to the location of the cross sectionnoted in FIG. 1. Support 120-1 may be between 1 mm and 100 mm in widthas indicated by distance 280. Cylindrical pouch cell 110 may be between300 mm and 1000 mm in height, as indicated by distance 282.

In order to make the charge of cylindrical pouch cell 110 usable,electrical connections need to be made with the anode and cathode ofactive components 112. Leads 250-1 and 250-2 may pass through insulativeseal 230 to the anode and cathode of active components 112,respectively. Insulative seal 230 may create a seal between cylindricalpouch cell 110 and the sealed housing. Insulative seal 230 may be apolymer based sealant and may be nonconductive. Sealed housing top 210may have an opening to allow leads 250 to protrude. Insulative seal 230may form a seal between cylindrical pouch cell 110 and sealed housingtop 210 such that an opening in sealed housing top 210 can be presentwithout pressurized liquid 130 escaping (or causing depressurization).Insulative seal 230 may be between 1 mm and 100 mm in height, asindicated by distance 281.

Present between cylindrical pouch cell 110 and sealed housing top 210may be top gap spaces 240 (e.g., 240-1, 240-2). In some embodiments,these gaps may be left empty, thus allowing pressurized liquid 130 toenter top gap spaces 240 and exert pressure on a top surface ofcylindrical pouch cell 110. Similarly, present between cylindrical pouchcell 110 and sealed housing bottom 220 may be bottom gap spaces 270(e.g., 270-1, 270-2, 270-3). In some embodiments, these gaps may be leftempty, thus allowing pressurized liquid 130 to enter bottom gap spaces270 and exert pressure on a bottom surface of cylindrical pouch cell110. Therefore, pressurized liquid 130 may exert pressure against therounded sidewall, a top circular surface, and a bottom circular surfaceof deformable pouch housing 116. In other embodiments, top gap spaces240, bottom gap spaces 270, or both may be filled or sealed such thatpressurized oil does not enter these regions. If pressurized liquid 130does not enter these regions, the isotropic pressure exerted bypressurized liquid 130 may only be exerted on the curved sidewall ofcylindrical pouch cell 110.

Base insulators 260 (260-1, 260-2) may provide a base for cylindricalpouch cell 110 to stand on to maintain a distance between cylindricalpouch cell 110 and sealed housing bottom 220. As illustrated, two baseinsulators 260 are present, in other embodiments, greater or fewernumbers of base insulators are present. Base insulators 260 may bebetween 1 mm and 100 mm in height, as indicated by distance 283.

FIG. 3 illustrates an embodiment of a pressurized battery module 300that includes cylindrical battery cell pouches. Pressurized batterymodule 300 is illustrated from a top view. Pressurized battery module300 includes multiple cylindrical pouch cell systems 100. For instance,hundreds of cylindrical pouch cell systems 100 may be present withinsealed housing 305. Sealed housing 305, which includes sealed housingtop 210 and sealed housing bottom 220. The packing ratio of thecylindrical pouch cells to pressurized liquid space may be between 10%and 90.7%. In some embodiments, the cylindrical pouch cell systems 100are arranged in offset rows. Cylindrical pouch cell systems 100 may bearranged to be parallel with each other.

In some embodiments, heating system 310 is present. Cylindrical pouchcells may function more efficiently when heated, such as to at least 60°C. Heating system 310 may include heating elements that are arranged onan exterior of sealed housing 305. Heating system 310 may alternativelyhave heating elements within sealed housing 305. In some embodiments,heating system 310 may include a circulator within sealed housing 305 tocirculate pressurized liquid 130 to more evenly heat pressurized liquid130. Pressurized liquid 130 may have a relatively high thermalconductivity, therefore active circulation of pressurized liquid 130 maynot be needed.

While FIGS. 1-3 are focused on cylindrical pouch cells, other shapes ofpouch cells may also be used, such as planar pouch cells. Such pouchcells may be stackable to form pouch cell arrays. FIG. 4 illustrates atop view of an embodiment of a planar cell array system 400. Multiplepouch cells, which may generally be rectangular and planar in shape, maybe stacked against each other. In the illustrated embodiment of FIG. 4,six pouch cells (410-1, 410-2, 410-3, 410-4, 410-5, and 410-6) arestacked against each other. In other embodiments, greater or fewernumbers of pouch cells may be present. In some embodiments, pouch cells410 may not be stacked to form arrays. Supporting plates 420-1 and 420-2may be used to support pouch cells 410 and hold in place within a sealedhousing.

Within each of pouch cells 410 may be a solid-state battery cell,meaning the cathode, anode, and electrolyte are solid, rather thanliquid or polymer based. For example, pouch cell 410-1 may use asulfur-based solid-state electrolyte. Pouch cell 410-1 may be a sulfuroxide battery pouch. Other types of battery pouches may be possible,such as non-solid state batteries.

Active components with each pouch cell of pouch cells 410 may besurrounded by deformable pouch housing of deformable pouch housings 411.Deformable pouch housings 411 may allow pressure exerted on an externalsurface of pouch cells 410 to be transferred to active components withineach pouch cell, thus causing the anode, cathode, and electrolyte to bepressed together. Therefore, deformable pouch housings 411 may not besufficiently rigid such that is can resist the pressure exerted bypressurized liquid without somewhat deforming. Center region 114 may beairspace or may be pole, such as a metallic pole.

Surrounding pouch cells 410 may be a thermally-conductiveelectrically-insulative pressurized liquid 130, such as an oil. This oilmay be pressurized such that hydraulic pressure is isotropically appliedto deformable pouch housings 411, at least along exposed surfaces of thepouch cells 410. This isotropic pressure exerted by pressurized liquid130 is visualized by arrows 440. In some embodiments, pressurized liquid130 is pressurized such that at least 1 MPa (145 pound-force per squareinch). Such a pressure may cause the electrolyte within activecomponents of pouch cells 410 to remain pressed against the cathode andanode.

Pressurized liquid 130 may exert isotropic pressure on exposed exteriorsurfaces of pouch cells 410. In some embodiments pouch cells 410 arepressed against each other such that pressurized liquid 130 only makescontact with the outermost pouch cells within an array, such as pouchcell 410-1 and 410-6. In such embodiments, pressure is applied to pouchcells 410-2 through 410-5 via the transfer of force through pouch cells410-1 and 410-6. In other embodiments, pressurized liquid can penetratebetween pouch cells within an array. For example, pressurized liquid maybe present between pouch cell 410-3 and pouch cell 410-4. In suchembodiments, pressurized liquid 130 may directly exert compressivepressure on each pouch cell 410.

A cross section 500 is illustrated in FIG. 4. FIG. 5 illustrates crosssection 500 of an embodiment of a planar battery cell pouch array.Visible in each pouch cell (such as pouch cell 410-1) is activecomponents 560. Active components 560, such as active components 560-1,may include an anode, a cathode, and an electrolyte.

Base insulator 540 may support each pouch cell 410 of the pouch cellarray and provide an insulative buffer between sealed housing bottom530-2 and pouch cells 410. Insulative seal 510 may provide a top supportand buffer between sealed housing top 530-1 and pouch cells 410. Leads520 may pass through insulative seal 510 and may electrically connectwith active components of pouch cells 410. Two leads may be present foreach pouch cell, a first lead to connect with an anode of a pouch celland a second lead to connect with a cathode of a pouch cell. Forsimplicity, only some of the illustrated leads have been labeled. Holescan be present with sealed housing top 530-1 to allow leads 520 to passto the exterior environment. Insulative seal 510 may seal the interiorenvironment of the sealed housing from the exterior to preventpressurized liquid 130 from escaping from the interior of thepressurized housing. Insulative seal 510 may be a polymer based sealantand may be nonconductive.

In some embodiments, pressurized liquid 130 may only apply pressure topouch cells 410 in the directions indicated by arrows 440. Pressurizedliquid 130 may be prevented from exerted force on a top and bottom ofeach pouch cell by insulative seal 510 and base insulator 540. In otherembodiments, pressurized liquid 130 may additionally apply pressure topouch cells 410 on a top, a bottom, or both (as illustrated by arrows550). By not sealing pouch cells 410 to insulative seal 510, baseinsulator 540, or both, pressurized liquid 130 may penetrate regionsbetween insulative seal 510, base insulator 540, and pouch cells 410,resulting in the isotropic pressure being exerted on the top, bottom, orboth of pouch cells 410.

FIG. 6 illustrates another embodiment of a planar battery cell poucharray cross section. The pouch cell array may be between 10 mm and 100mm in width. The pouch cell array may be between 300 mm and 3000 mm inheight. Insulative seal 510 may be between 1 mm and 100 mm in height.Base insulator 540 may be between 1 mm and 100 mm in height. Suchmeasurements may be varied based on the specific application of thebattery and battery module in which the pouch arrays are incorporated.

FIG. 7 illustrates an embodiment of a pressurized battery module 700that includes planar battery cell pouch arrays. Pressurized batterymodule 700 is illustrated from a top view. Pressurized battery module700 includes multiple pouch cell array systems 400. For instance,hundreds of pouch cell array systems 400 may be present within sealedhousing 305. Sealed housing 305, which includes sealed housing top 530-1and sealed housing bottom 530-2. The packing ratio of the planar pouchcell arrays to pressurized liquid space may be between 10% and 90%. Insome embodiments, the pouch cell array systems 400 are arranged in rowsor a grid. Pouch cell array systems 400 may be arranged to be verticallyparallel with each other.

In some embodiments, heating system 310 is present. Cylindrical pouchcells may function more efficiently when heated, such as to at least 60°C. Heating system 310 may include heating elements that are arranged onan exterior of sealed housing 305. Heating system 310 may alternativelyhave heating elements within sealed housing 305. In some embodiments,heating system 310 may include a circulator within sealed housing 305 tocirculate pressurized liquid 130 to more evenly heat pressurized liquid130. Pressurized liquid 130 may have a relatively high thermalconductivity, therefore active circulation of pressurized liquid 130 maynot be needed.

While battery cells as detailed herein may be housed in a pressurizedenvironment, when such battery cells are manufactured, part of themanufacturing process, which can be referred to as an activationprocess, may involve a process being performed to form improved contactbetween a battery cell's electrolyte and the battery cell's anode and/orbetween the battery cell's electrolyte and the battery cell's cathode.As previously detailed, various types of batteries, such as cylindrical,jelly-roll battery cells, may function more effectively when pressure isapplied to press the active components (i.e., cathode and/or anode) ofthe battery cell against the electrolyte. Further, some of such types ofbattery cells in use of Sulfur or oxide based solid-state electrolytemay also function more effectively when operated at a relatively hightemperature (e.g., above 60° C.). To manufacture such battery cells,improved contact between the active components and the electrolyte maybe achieved by applying a pressure and temperature greater than thepressure and temperature that is to be applied during subsequentoperating conditions.

Using a thermally-conductive electrically-insulative liquid, aconsistent pressure may be applied to an exterior of each battery celland, possibly, thermal energy may be evenly and efficiently dispersedamong battery cells. This pressure and increased temperature may bemaintained for a period of time, followed by the pressure being releasedand the temperature being decreased. Once this process has beenperformed, the battery cell may be referred to as semi-active.

The semi-active battery cell may be permanently installed within abattery module. Within the battery module, the semi-active battery cellmay be re-pressurized, however not to as high of a pressure as duringthe activation process. The temperature may also be increased duringoperation, however, possibly not up to the pressure level of theactivation process. The battery cell may exhibit improved operatingcharacteristics (including greater power density and/or greater energydensity) than if the activation process is not performed.

Further detail regarding such systems and processes is provided inrelation to FIGS. 8-11. FIG. 8 illustrates a side view of an embodimentof a battery cell activation system 800. Battery cell activation system800 may include: sealable housing 810 (which includes sidewall 810-1 andsidewall 810-2); cap 820; heating elements 815; top battery cell support830; bottom battery support 835; and liquid cavity 840.

Sealable housing 810 may be a rigid housing which can be sealed andmaintain an increased pressure level within sealed housing 810 ascompared to the external ambient environment. Sealable housing 810 maybe metal. Within one or more sidewalls of sealable housing 810 (such assidewalls 810-1 and 810-2) may be heating elements 815. Heating elements815 may be resistive heating elements, which can also be referred to asJoule heating or Ohmic heating elements, which produce heat when anelectrical current is present. Heating elements 815 may be dispersedthroughout sidewalls 810-2 and 810-2 such that heat is approximatelyevenly applied to liquid cavity 840.

Sealable housing 810 may interface with removable cap 820. Cap 820 maybe removable such that battery cell 850 may be removably inserted withinliquid cavity 840. Cap 820 may seal with sealable housing 810 such thatpressure created within liquid cavity 840 does not dislodge cap 820.While the illustrated embodiment shows cap 820 atop sealable housing810, it should be understood that an access panel elsewhere on sealablehousing 810 may be used instead of on top.

Within sealable housing 810 may be various supports, such as top batterycell support 830 and bottom battery support 835. Bottom battery support835 may hold battery cell 850 elevated from a bottom of liquid cavity840. Top battery cell support 830 may be affixed to cap 820 and may helphold battery cell 850 in a fixed location within liquid cavity 840.

Battery cell 850 may be a cylindrical battery cell. A “jelly-roll” stylebattery cell may be constructed by different materials being layered oneach other then rolled into a cylinder and placed in a cylindricalhousing. For example, a first layer may be an anode layer, a secondlayer may be an electrolyte layer, and a third layer may be a cathodelayer. Additional layers may be present, such as interface layersbetween the anode and electrolyte and/or between the cathode and theelectrolyte. Battery cell 850 may be wrapped in a flexible membrane. Aflexible membrane may prevent liquid from penetrating to within thecylindrical battery cell. The flexible membrane may provide littleresistance to pressure and, thus, may allow external pressure to exertpressure on the layer components of the cylindrical battery cell. Suchpressure may result in the anode being pressed to the electrolyte and/orthe cathode being pressed to the electrolyte.

Battery cell 850 may be a solid state battery cell. The electrolyte usedmay be a Li-ion-conductive polymer, or sulfur/oxide based solid-stateelectrolyte. The power density of a battery cell that used such anelectrolyte may be increased by a large amount of contact beingpresented between the electrolyte, the anode, and the cathode.

Liquid cavity 840 may be formed by an open space within sealable housing810. Liquid cavity 840 may be filled with a liquid that is electricallynonconductive and thermally conductive. In some embodiments, oil isused. The liquid used to fill liquid cavity 840 may be the same type ofliquid used to fill sealed housing 305. Liquid cavity 840 may be kept atleast partially filled with liquid. Battery cell 850 may be inserted,the remained of liquid cavity 840 filled with liquid, then sealablehousing 810 pressurized. While pressurized heat may be applied tobattery cell 850 via heating elements 815. Heating elements 815 may beatsealable housing 810, which heats liquid in liquid cavity 840, which, inturn, heats battery cell 850. The heat may be well dispersed such thatapproximately the same temperature liquid is present around the sides,top, and bottom of battery cell 850. By using liquid to transfer theheat between the heating elements 815 and battery cell 850 rather thanair, the heat is transferred significantly quicker, thus allowingbattery cell 850 to heat up quicker.

In some embodiments, rather than heating elements 815 being embedded insidewalls 811, heating elements 815 may be external to sidewalls 811 bybeing located with liquid cavity 840 or outside of sealable housing 810.In such an embodiment, heating elements 815 may be wrapped against anexternal surface of sealable housing 810.

FIG. 9 illustrates a top view of an embodiment of a battery cellactivation system 900. Battery cell activation system 900 may representan embodiment of battery cell activation system 800 of FIG. 8. Batterycell activation system 900 may include liquid pump 905. Liquid pump 905may serve multiple purposes: liquid pump 905 may be used to fill liquidcavity 840 completely or nearly completely with liquid after batterycell 850 has been positioned within liquid cavity 840; liquid pump 905may be used to increase, decrease, and control the pressure withinsealable housing 810 after sealable housing 810 has been sealed; andliquid pump 905 may be used to circulate liquid within liquid cavity840. Liquid pump 905 may have a connection with liquid cavity 840 viapiping 910 that allows liquid to be pumped into and, possibly, pumpedout of liquid cavity 840.

FIG. 10 illustrates a side view of an embodiment of a battery cellactivation system 1000. Battery cell activation system 1000 may functionsimilarly to battery cell activation system 800 (and possibly 900) ofFIGS. 8 and 9, respectively. Battery cell activation system 1000 allowsmultiple battery cells to be activated simultaneously. In theillustrated example, four battery cells 850 are present within sealablehousing 1010. This number of battery cells is for example purposes only;in other embodiments, fewer or greater numbers of battery cells may bepresent, such as tens or even hundreds of battery cells. Since liquidwithin liquid cavity 1020 is used to apply pressure to external surfacesof battery cells 850, the pressure is isotropic on the external batterycell surfaces.

FIG. 11 illustrates an embodiment of a method 1100 for activating abattery cell by increasing an amount of contact between an electrolyteand active materials of a battery cell. Method 1100 may be performedusing the systems and devices detailed in FIGS. 8-10. Method 1100 may beused as part of a manufacturing process to activate or condition one ormore battery cells for use in systems and devices as detailed inrelation to FIGS. 1-7.

At block 1105, a battery cell, which may use a solid Li-ion conductivepolymer electrolyte, may be immersed in liquid within a housing that canbe sealed. The liquid may be a non-electrically conductive, thermallyconductive liquid. This liquid may be a type of oil. The battery cellimmersed at block 1105 has an electrolyte, anode, and cathode, which maybe manufactured as a jelly-roll style cylindrical pouch-style batterycells or planar pouch cells. The battery cell immersed at block 1105 maybe functional, however the functionality of the battery cell may beimproved by increasing the amount of contact between the anode and theelectrolyte and/or the cathode and the electrolyte.

At block 1110, the housing may be sealed with the immersed battery cellinside. At this block, there may be some air space within the sealedhousing. In other embodiments, no air space may be present. If someamount of air space is present, at block 1115, additional liquid may bepumped or otherwise added to the interior of the sealed housing. Block1115 may involve allowing the air to escape. Following block 1115, allof the air or substantially all of the air may be removed such that thebattery cell is fully immersed in the liquid (e.g., all externalsurfaces of the battery are in contact with the liquid).

At block 1120, the liquid may be pressurized within the sealed housing,such as to between 1 MPa and 300 MPa, depending on battery cell type. Byvirtue of the liquid being pressurized, the pressure may be appliedisotropically to the external surfaces (top, bottom, and/or sidewalls)of the battery cell that is immersed in the liquid. The pressure appliedat block 1120 may be at least 1 MPa. At block 1125, the liquid may beheated such that the heat is applied approximately isotropically to theexternal surfaces of the immersed battery cell. In some embodiments, theliquid is heated to between 100° C.-200° C. The battery cell may beheated rapidly compared to if the battery cell was surrounded by airsince the liquid has a higher thermal conductance than air. Blocks 1120and 1125 may be reversed in order or may be performed concurrently invarious embodiments. In some embodiments, the liquid may not be heated.The battery cell may remain within the pressurized and/or heated liquidfor a period of time, such as between one and ten minutes. Pressure maybe created and maintained using a liquid pump. Heat may be generatedusing one or more Joule heating elements which may be within the wallsof the sealed housing, inside of the sealed housing, or external to thesealed housing.

At block 1130, the liquid may be cooled, if heated, and depressurized tothe ambient environment's pressure. In some embodiments, the liquid isactively cooled, in other embodiments the liquid is allowed to cool byventing heat into the ambient environment.

At block 1135, the battery cell may be removed from the liquid. Thebattery cell may be considered semi-activated at this point in time.That is, by blocks 1105-1130 having been performed, the battery has nowbeen semi-activated. The battery cell may be considered activated whenit is installed in a pressurized environment, such as detailed at block1150. At block 1140, the semi-activated battery cell may be cleaned toremove residual liquid on the exterior surfaces of the battery cell.

At block 1145, the semi-activated battery may be installed within asealable housing in which the battery cell is to charged and discharged.This housing is separate and distinct from the housing used for blocks1105-1135. The housing used at block 1145 may be a housing that is tofunction as part of a battery module. Such a sealable housing may belocated on-board a vehicle. For example, sealed housing 305 of FIGS. 3and 7 may be used. Once the battery cell has been installed within thesealable housing, the sealable housing may be sealed with the batterycell inside at block 1150. Liquid, such as oil, which may be the sameform of liquid used at block 1120 may be present within the sealablehousing such that all or most of the space surrounding the battery cellis occupied by liquid. After the battery cell is inserted into thehousing, the amount of liquid within the sealable housing may be toppedoff or all of the liquid may be added.

At block 1150, the liquid within the housing may be pressurized, such asusing a pump. Once the liquid has been pressurized to the desiredpressure, the sealable housing may be sealed at block 1150, possiblypermanently. The battery cell may now be considered activated. As such,the pressure may be retained by virtue of the sealable housingpreventing the pressure from escaping. The pressure created at block1150 may be less pressure than the pressure applied at block 1120.Similarly, the liquid within the housing may be heated, such as usingone or more heating elements, such as heating system 310. The heatcreated at block 1150 may be less than the heat applied at block 1125such that the operating temperature is below the temperature at whichthe battery was activated at block 1125. Heat may be applied to keep thebattery within a desired temperature operating range.

At block 1155, the activated battery cell may undergo charge anddischarge cycles, such that the activated battery cell, which is withinthe isotropic pressurized environment, creates electricity that can beused to power a system or device, such as an electric vehicle.

The methods, systems, and devices discussed above are examples. Variousconfigurations may omit, substitute, or add various procedures orcomponents as appropriate. For instance, in alternative configurations,the methods may be performed in an order different from that described,and/or various stages may be added, omitted, and/or combined. Also,features described with respect to certain configurations may becombined in various other configurations. Different aspects and elementsof the configurations may be combined in a similar manner. Also,technology evolves and, thus, many of the elements are examples and donot limit the scope of the disclosure or claims.

Specific details are given in the description to provide a thoroughunderstanding of example configurations (including implementations).However, configurations may be practiced without these specific details.For example, well-known circuits, processes, algorithms, structures, andtechniques have been shown without unnecessary detail in order to avoidobscuring the configurations. This description provides exampleconfigurations only, and does not limit the scope, applicability, orconfigurations of the claims. Rather, the preceding description of theconfigurations will provide those skilled in the art with an enablingdescription for implementing described techniques. Various changes maybe made in the function and arrangement of elements without departingfrom the spirit or scope of the disclosure.

Also, configurations may be described as a process which is depicted asa flow diagram or block diagram. Although each may describe theoperations as a sequential process, many of the operations can beperformed in parallel or concurrently. In addition, the order of theoperations may be rearranged. A process may have additional steps notincluded in the figure. Furthermore, examples of the methods may beimplemented by hardware, software, firmware, middleware, microcode,hardware description languages, or any combination thereof. Whenimplemented in software, firmware, middleware, or microcode, the programcode or code segments to perform the necessary tasks may be stored in anon-transitory computer-readable medium such as a storage medium.Processors may perform the described tasks.

Having described several example configurations, various modifications,alternative constructions, and equivalents may be used without departingfrom the spirit of the disclosure. For example, the above elements maybe components of a larger system, wherein other rules may takeprecedence over or otherwise modify the application of the invention.Also, a number of steps may be undertaken before, during, or after theabove elements are considered.

What is claimed is:
 1. A pressurized battery module, comprising: asealed battery module housing, comprising a housing top and a housingbottom; a plurality of support pillars; a plurality of cylindricalbattery cell pouches, wherein each cylindrical battery cell pouch issupported by a subset of the plurality of support pillars; a pluralityof insulative seals, wherein: each insulative seal of the plurality ofinsulative seals is located between a cylindrical battery cell pouch ofthe plurality of cylindrical battery cell pouches and the housing top; aplurality of base insulators, wherein: each base insulator of theplurality of base insulators is located between a cylindrical batterycell pouch of the plurality of cylindrical battery cell pouches and thehousing bottom; and a liquid that is pressurized within the sealedhousing, wherein the liquid exerts pressure on an external surface ofeach cylindrical battery cell pouch of the plurality of cylindricalbattery cell pouches.
 2. The pressurized battery module of claim 1,wherein three support pillars of the plurality of support pillarssupport each cylindrical battery cell pouch of the plurality ofcylindrical battery cell pouches within the sealed battery modulehousing.
 3. The pressurized battery module of claim 1, wherein theliquid exerts isotropic pressure to a curved sidewall of eachcylindrical battery cell pouch of the plurality of cylindrical batterycell pouches.
 4. The pressurized battery module of claim 3, wherein theliquid exerts isotropic pressure on a top, a bottom, and a curvedsidewall of each cylindrical battery cell pouch of the plurality ofcylindrical battery cell pouches.
 5. The pressurized battery module ofclaim 1, wherein the liquid is an electrically-insulative oil.
 6. Thepressurized battery module of claim 1, wherein a center region of eachcylindrical battery cell pouch of the plurality of cylindrical batterycell pouches is an airspace.
 7. The pressurized battery module of claim1, wherein a center region of each cylindrical battery cell pouch of theplurality of cylindrical battery cell pouches is a metallic pole.
 8. Thepressurized battery module of claim 1, further comprising: a pluralityof leads; and a polymer-based sealant, wherein the polymer-based sealantcreates a seal for each cylindrical battery cell pouch of the pluralityof cylindrical battery cell pouches through which a lead of theplurality of leads passes between the cylindrical battery cell pouch andan external environment outside of the sealed battery module housing. 9.The pressurized battery module of claim 1, wherein each pouch cellcomprises a sulfur-based solid-state electrolyte.
 10. The pressurizedbattery module of claim 1, wherein the sealed battery module housing isconnected with a heating system that comprises a heating element and acirculator.
 11. A pressurized battery module system, comprising: aheating system, comprising: one or more heating elements; and acirculator configured to circulate a liquid that is pressurized; asealed battery module housing, comprising a housing top and a housingbottom; a plurality of support pillars; a plurality of cylindricalbattery cell pouches, wherein each cylindrical battery cell pouch issupported by a subset of the plurality of support pillars; a pluralityof insulative seals, wherein: each insulative seal of the plurality ofinsulative seals is located between a cylindrical battery cell pouch ofthe plurality of cylindrical battery cell pouches and the housing top; aplurality of base insulators, wherein: each base insulator of theplurality of base insulators is located between a cylindrical batterycell pouch of the plurality of cylindrical battery cell pouches and thehousing bottom; and the liquid that is pressurized within the sealedhousing, wherein the liquid exerts pressure on an external surface ofeach cylindrical battery cell pouch of the plurality of cylindricalbattery cell pouches.
 12. The pressurized battery module system of claim11, wherein the one or more heating elements are exterior to the sealedbattery module housing.
 13. The pressurized battery module system ofclaim 11, wherein three support pillars of the plurality of supportpillars support each cylindrical battery cell pouch of the plurality ofcylindrical battery cell pouches within the sealed battery modulehousing.
 14. The pressurized battery module system of claim 11, whereinthe liquid exerts isotropic pressure to a curved sidewall of eachcylindrical battery cell pouch of the plurality of cylindrical batterycell pouches.
 15. The pressurized battery module system of claim 14,wherein the liquid exerts isotropic pressure on a top, a bottom, and acurved sidewall of each cylindrical battery cell pouch of the pluralityof cylindrical battery cell pouches.
 16. The pressurized battery modulesystem of claim 15, wherein the liquid is an electrically-insulativeoil.
 17. The pressurized battery module system of claim 16, furthercomprising: a plurality of leads; and a polymer-based sealant, whereinthe polymer-based sealant creates a seal for each cylindrical batterycell pouch of the plurality of cylindrical battery cell pouches throughwhich a lead of the plurality of leads passes between the cylindricalbattery cell pouch and an external environment outside of the sealedbattery module housing.
 18. The pressurized battery module system ofclaim 17, wherein a center region of each cylindrical battery cell pouchof the plurality of cylindrical battery cell pouches is an airspace. 19.The pressurized battery module system of claim 17, wherein a centerregion of each cylindrical battery cell pouch of the plurality ofcylindrical battery cell pouches is a metallic pole.
 20. The pressurizedbattery module system of claim 11, wherein each pouch cell comprises asulfur-based solid-state electrolyte.